net/sunrpc/sysctl.c

   1 /*
   2  * linux/net/sunrpc/sysctl.c
   3  *
   4  * Sysctl interface to sunrpc module.
   5  *
   6  * I would prefer to register the sunrpc table below sys/net, but that's
   7  * impossible at the moment.
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/linkage.h>
  12 #include <linux/ctype.h>
  13 #include <linux/fs.h>
  14 #include <linux/sysctl.h>
  15 #include <linux/module.h>
  16
  17 #include <asm/uaccess.h>
  18 #include <linux/sunrpc/types.h>
  19 #include <linux/sunrpc/sched.h>
  20 #include <linux/sunrpc/stats.h>
  21
  22 /*
  23  * Declare the debug flags here
  24  */
  25 unsigned int    rpc_debug;
  26 unsigned int    nfs_debug;
  27 unsigned int    nfsd_debug;
  28 unsigned int    nlm_debug;
  29
  30 #ifdef RPC_DEBUG
  31
  32 static struct ctl_table_header *sunrpc_table_header;
  33 static ctl_table                sunrpc_table[];
  34
  35 void
  36 rpc_register_sysctl(void)
  37 {
  38         if (!sunrpc_table_header)
  39                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
  40 }
  41
  42 void
  43 rpc_unregister_sysctl(void)
  44 {
  45         if (sunrpc_table_header) {
  46                 unregister_sysctl_table(sunrpc_table_header);
  47                 sunrpc_table_header = NULL;
  48         }
  49 }
  50
  51 static int
  52 proc_dodebug(ctl_table *table, int write, struct file *file,
  53                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  54 {
  55         char            tmpbuf[20], c, *s;
  56         char __user *p;
  57         unsigned int    value;
  58         size_t          left, len;
  59
  60         if ((*ppos && !write) || !*lenp) {
  61                 *lenp = 0;
  62                 return 0;
  63         }
  64
  65         left = *lenp;
  66
  67         if (write) {
  68                 if (!access_ok(VERIFY_READ, buffer, left))
  69                         return -EFAULT;
  70                 p = buffer;
  71                 while (left && __get_user(c, p) >= 0 && isspace(c))
  72                         left--, p++;
  73                 if (!left)
  74                         goto done;
  75
  76                 if (left > sizeof(tmpbuf) - 1)
  77                         return -EINVAL;
  78                 if (copy_from_user(tmpbuf, p, left))
  79                         return -EFAULT;
  80                 tmpbuf[left] = '\0';
  81
  82                 for (s = tmpbuf, value = 0; '0' <= *s && *s <= '9'; s++, left--)
  83                         value = 10 * value + (*s - '0');
  84                 if (*s && !isspace(*s))
  85                         return -EINVAL;
  86                 while (left && isspace(*s))
  87                         left--, s++;
  88                 *(unsigned int *) table->data = value;
  89                 /* Display the RPC tasks on writing to rpc_debug */
  90                 if (table->ctl_name == CTL_RPCDEBUG) {
  91                         rpc_show_tasks();
  92                 }
  93         } else {
  94                 if (!access_ok(VERIFY_WRITE, buffer, left))
  95                         return -EFAULT;
  96                 len = sprintf(tmpbuf, "%d", *(unsigned int *) table->data);
  97                 if (len > left)
  98                         len = left;
  99                 if (__copy_to_user(buffer, tmpbuf, len))
 100                         return -EFAULT;
 101                 if ((left -= len) > 0) {
 102                         if (put_user('\n', (char __user *)buffer + len))
 103                                 return -EFAULT;
 104                         left--;
 105                 }
 106         }
 107
 108 done:
 109         *lenp -= left;
 110         *ppos += *lenp;
 111         return 0;
 112 }
 113
 114
 115 static ctl_table debug_table[] = {
 116         {
 117                 .ctl_name       = CTL_RPCDEBUG,
 118                 .procname       = "rpc_debug",
 119                 .data           = &rpc_debug,
 120                 .maxlen         = sizeof(int),
 121                 .mode           = 0644,
 122                 .proc_handler   = &proc_dodebug
 123         },
 124         {
 125                 .ctl_name       = CTL_NFSDEBUG,
 126                 .procname       = "nfs_debug",
 127                 .data           = &nfs_debug,
 128                 .maxlen         = sizeof(int),
 129                 .mode           = 0644,
 130                 .proc_handler   = &proc_dodebug
 131         },
 132         {
 133                 .ctl_name       = CTL_NFSDDEBUG,
 134                 .procname       = "nfsd_debug",
 135                 .data           = &nfsd_debug,
 136                 .maxlen         = sizeof(int),
 137                 .mode           = 0644,
 138                 .proc_handler   = &proc_dodebug
 139         },
 140         {
 141                 .ctl_name       = CTL_NLMDEBUG,
 142                 .procname       = "nlm_debug",
 143                 .data           = &nlm_debug,
 144                 .maxlen         = sizeof(int),
 145                 .mode           = 0644,
 146                 .proc_handler   = &proc_dodebug
 147         },
 148         { .ctl_name = 0 }
 149 };
 150
 151 static ctl_table sunrpc_table[] = {
 152         {
 153                 .ctl_name       = CTL_SUNRPC,
 154                 .procname       = "sunrpc",
 155                 .mode           = 0555,
 156                 .child          = debug_table
 157         },
 158         { .ctl_name = 0 }
 159 };
 160
 161 #endif